Dental instrument

ABSTRACT

A dental instrument for dispensing tooth filling material into a cavity and for compacting the filling material in the cavity. The compacting element of the instrument ejects the tooth filling material and then closes a dispensing opening of the filling material container so the instrument can be used to compact the dispensed filling material. The container and compacting element are releasably secured to the instrument as a unit with the compacting element closing the dispensing opening of the container. The container can be prefilled with the ingredients of the tooth filling amalgam and can be shaken to mix same, or alternatively, the container can be filled with mixed amalgam just before use.

United States Patent [1 1 Noll et a1.

[ Aug. 14, 1973 DENTAL INSTRUMENT [76] Inventors: Carroll G. Noll, 4196Abinadi Rd.;

Alvan M. Morris, 7148 Loch Lomond Dr., both of Bethesda, Md.

[22] Filed: Mar. 3, 1972 [21] App]. No.: 231,681

Primary Examiner-Robert Peshock Att0mey-Hyman Hurvitz ABSTRACT A dentalinstrument for dispensing tooth filling material into a cavity and forcompacting the filling material in the cavity. The compacting element ofthe instrument ejects the tooth filling material and then closes adispensing opening of the filling material container so the instrumentcan be used to compact the dispensed filling material. The container andcompacting element are releasably secured to the instrument as a unitwith the compacting element closing the dispensing opening of thecontainer. The container can be prefilled with the ingredients of thetooth filling amalgam and can be shaken to mix same, or alternatively,the container can be filled with mixed amalgam just before use.

15 Claims, 6 Drawing Figures DENTAL INSTRUMENT This invention relates toa dental instrument for dispensing a tooth-filling material and forcompacting the filling material into a cavity of a tooth.

More specifically, the invention relates to an instrument to be held inthe hand of a dentist for dispensing a tooth-filling material such asamalgam, and in which the compacting implement ejects amalgam from anamalgam container mounted on the instrument.

In the past, a dentist filling a tooth has required several instruments.In addition, the conventional amalgam used for filling a tooth cavitymust first be mixed and the amalgam must be pressed into the toothcavity before the amalgam sets. Hence, it has been necessary for thedentist to first mix the amalgam, use a first instrument to press theamalgam into the tooth cavity, and use a second instrument to compactthe amalgam into the cavity and smooth the exposed surface of theamalgam. This procedure usually requires an assistant who mixes theamalgam and thereafter, the amalgam is picked up in an ejector, andsubsequently a separate compactor and smoother is used. Such changing ofinstruments increases the time required to fill a tooth andcorrespondingly is time consuming'and adds to the discomfort of thepatient.

The present invention overcomes the shortcoming of the prior techniquesby providing a dental instrument in which an amalgam container isreleasably connected to the instrument and in which dispensing andcompacting the amalgam can be accomplished without removing theinstrument from the patients mouth. Since the compacting tool is alsothe ejector for the amalgam, the instrument is maintained in essentiallythe same position relative to the tooth and filling and compacting theamalgam into the tooth cavity can be accomplished quite quickly withminimum discomfort to the patient and without the need for an assistant.

The amalgam dispenser is of itself unique and includes a container inthe form of a cartridge with a follower or piston via which the amalgamis urged toward a dispensing opening of the container. The dispensingopening is normally sealed by the compacting tool which takes the formof a plunger and is also used to eject amalgam through the dispensingopening. The amalgam container is arranged to be quickly secured to theinstrument and can be easily removed when the supply of amalgam isdepleted. The amalgam container can be filled with prepared amalgam atthe beginning of the tooth filling operation, for example, by thedentist's assistant, and thereafter, the assistant is no longerrequired. Alternatively, the container can be prefilled'.

with the components of the amalgam system and the components can bemixed by shakingin the usual amalgam mixer. Advantageously, the amalgamdispenser is of the throw-away type so the dentist need not be concernedabout cleaning hardened amalgam from the container.

Amalgam is dispensed from the container byreciprocatingthe .compactingtool to withdraw the tool to aposition out of the path of amalgam forcedtowardthe dispensing opening by the piston. Then the plungeris advancedthereby ejecting a quantity of amalgam and at the same time advancingthe compacting toolto an exposed position in which it is locked soitcanbe used to compact the amalgam into the tooth cavity. Advancing andretracting the plungebcompactor is accomplished by manipulating asuitable control, for example, a valve on the handle of the tool toselectively actuate a motor, for example, an air motor contained withinthe tool. Where an air motor is used, this motor is, of course,compatible with the air supply available at the dentists office.

Correspondingly, an object of this invention is a dentaI instrument inwhich the compacting element or tool of the instrument also serves toeject a tooth-filling material from an amalgam container which can bereleasably secured to the instrument.

Another objectis the container for tooth-filling material which isadapted to be secured to a dental instrument and in which the dispensingopening of the container is closed by an element which is also used tocompact and tool the tooth filling material into a tooth cavity.

Numerous other objects, features and advantages of the invention willbecome apparent with reference to the drawings which form a part of thespecification and in which:

FIG. 1 is a pictorial view of the dentists instrument of this invention;

FIG. 2 is a partial view in vertical section taken along line 2 2 ofFIG. 1 and showing the compactor tool extended;

FIG. 3 is a partial view in horizontal section taken along line 3 3 ofFIG. 2;

FIG. 4 is a view corresponding to FIG. 2 and showing the compactor toolretracted;

FIG. 5 is a view corresponding to FIG. 2 and showing the manner in whichthe amalgam container is inserted in the tool; and

FIG. 6 is a bottom plan view of the amalgam container.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT Referring now to thedrawings in detail, there is shown a dental instrument I in accordancewith this invention. Instrument 1 includes a hollow handle 2 inclinedupwardly from and fixed to a hollow housing 3.

Within housing 3 is a generally triangularly shaped cam plate 4connected to wall 5 of the housing for pivotal movement by a pivot 6including screw and nut assembly. Cam plate 4 is bent to provide anoffset from end 7, which is flat and is in a plane adjacent a side wall8 of the housing. The offset front end 7 has a horizontal slot 9 formedtherein which opens toward the front of instrument 1. Fonned in the bodyof cam plate 4 at a location spaced from front end 'I is a curved camslot 10 with closed ends.

At the front of instrument I is a latch element ll in the form of arectangular plate which is slidable in a pair of facing grooves 12 atthe front of the housing. A stop 13 is provided at the bottom of thegrooves .to prevent separation of the latch from the housing.

A bottom wall 14 of housing 3 has .an offset front portion 15 to supporta container 16 containing toothfilling material- 17, which can beamalgam. At the offset, bottom wall l4 presents a shoulder .18 whichlimits the distance that container 16 can be inserted into .the housingfrom the front of thehousing. Adjacent bottom wall is a compressionspring 19 which seats against rear wall 20 of the housing and isretained against displacement by a projecting tip 21.

Extending through slot is a transversely extending end 22 of a pistonrod 23. Rod 23 is connected to a piston 24 located in a cylinder 25formed in handle 2.

Disposed in a chamber 26 spaced from cylinder 25 is a valve element 27having a cylindrical groove 28. Valve element 27 is connected to a knob29 on the outside of handle 2 via a stem which extends through a slot inthe side wall of the handle. A source of pressure air (not shown)communicates with a tube 30 that extends through the handle and isconnected to a passage 31 which communicates with groove 28 in allpositions of valve element 27. The head end of cylinder 25 communicateswith chamber 26 via a conduit 32 and the piston rod end of cylinder 25communicates with chamber 26 via a conduit 33. The passage and conduits31 33 can be formed in the side wall of handle 2, as shown at FIGS. 2and 4. It is to be noticed that the ends of passages 32 and 33, whichcommunicate with chamber 26, are spaced apart a distance slightlygreater than the length of groove 28 so groove 28 cannot communicatewith both passages simultaneously.

Mounted on side wall 8 is a vibrator 34 which can take the form of avibrating air motor connected to an air supply (not shown) via suitabletubing 35 and a control valve 36.

THE AMALGAM CONTAINER As shown in FIGS. 5 and 6, amalgam container 16 isgenerally rectangular and takes the form of a casing having a chamber 40therein which can be either rectangular or cylindrical. Chamber 40 opensthrough an end 39 of the container and this opening has the samecross-sectional configuration as the chamber so a piston 41 of the samecross-sectional configuration as the chamber 40 and which initiallycloses the chamber can slide through the chamber. Chamber 40 terminatesadjacent a front wall 42 of the container. Communicating with chamber 40at a location adjacent front wall 42 is a dispensing opening 43 havingits axis transverse to the length of the chamber and defined in part bya tubular wall 44. There is also a second opening 45 in the oppositewall of the container, opening 45 having its axis aligned with opening43. Extending through openings 45 and 43 is a cylindrical elongatedcompactor element 46 which closes and seals both the openings. Compactorelement 46 has a working face 47 of a desired con figuration for toolingthe amalgam after it is dispensed. As shown in FIG. 3, a pin 48 projectsradially from tool element 46 at a location adjacent the upper end ofthe compactor element and extends into the slot 9 at the front of camplate 4.

The amalgam 17, or other tooth-filling material within chamber 40, canbe placed in the chamber manually by the dentist. The amalgam is mixedin the customary manner. Alternatively, chamber 40 can initially containthe ingredients necessary to form the amalgam mix, and the entirecontainer 16 can be shaken to mix the amalgam directly within thechamber 40.

OPERATION AND USE The first step in use of the dental instrument 1 is toload container 16 into housing 3 of the instrument. This isaccomplished, as shown in FIG. 5, by first lifting latch 11 and thensliding the container into the housing so it rests on bottom wall of thehousing and end 39 of the container abuts shoulder 18 of the bottom wallof the housing. The length of the container between end 42 and end 39 isessentially the same as the distance between shoulder 18 and the insidesurface of latch 11 whereupon, positioning edge 48 against shoulder 18and lowering latch 11 to the position of FIGS. 2 0r 4 secures container16 in position on the dental instrument. As the container assembly ismoved into the housing, pin 48 slides into slot 9 at the front end ofcam plate 4. With the container so positioned, compactor element 46 isconnected to cam plate 4 via pin 48 and slot 9, and the compactorelement will be raised and lowered as the cam plate is pivoted betweenthe positions of FIGS. 4 and 5.

In use, to dispense amalgam, knob 29 is moved from the position of FIG.2 to the position of FIG. 4 so groove 28 of valve element 27communicates with passages 31 and 33, whereupon air under pressure isintroduced to the rod end of cylinder 25 and causes piston 24 to retractto the FIG. 4 position. During such movement of the piston, cam plate 4is pivoted in a clockwise direction by engagement of end 22 of pistonrod 23 in slot 10. The upward movement of the forward end 7 of the camplate retracts compactor element 46 to the FIG. 4 position. During suchmovement of the piston, cam plate 4 is pivoted in a clockwise directionby engagement of end 22 of piston rod 23 in slot 10. The upward movementof the forward end 7 of the cam plate retracts compactor element 46 tothe FIG. 4 position. In the FIG. 4 position of the compactor element,dispensing opening 43 is unobstructed as is at least a portion of end 50of chamber 40. This permits spring 19 to force piston 41 further intochamber 40 so amalgam flows toward the dispensing opening and into thepath of travel of compactor 46. Then, when valve 29 is moved to theposition of FIG. 2 by manipulating knob 29, groove 28 of valve element27 communicates passage 32 with passage 31 so air under pressure isintroduced into the head end of cylinder 25, thereby forcing piston 24downwardly toward cam plate 4. The curved slot 10 causes cam plate 4 tomove to the position of FIG. 2 in which compactor 46 extends through thedispensing opening 43 and projects a substantial distance from theopening. During its movement toward and through dispensing opening 43,the tool ejects a quantity of amalgam through the tube 44.

If more amalgam is needed, knob 29 is shifted to retract compactorelement 46 so additional amalgam 17 flows toward the dispensing openingunder the action of spring 19 on piston 41. Knob 29 is then shifted toextend compacting element 46 and dispense an additional quantity ofamalgam. The tube 44 which surrounds dispensing opening 43 permits thedentist to position the end of the tube adjacent the cavity so theamalgam will be dispensed directly into the cavity. Since compactor 46is exposed immediately after the amalgam is dispensed the dentist can,without removing the instrument from the patient's mouth, press theamalgam into the cavity or otherwise tool the amalgam with the compactorelement.

The shape of the lower end of cam slot 10 is such that the cam plate 4is locked in its extended position, and correspondingly, forces exertedon the working face of compactor element 46 cannot move the cam plate.This permits application of pressure to the compacting element withoutdanger of movement of the compacting element from its extended position.To assure complete filling of a cavity with the amalgam, the dentist mayopen valve 36 to actuate the vibrator 34. The vibrator 34 vibrates theentire instrument 1 including the compactor element 46 and therebyassists compacting the amalgam to completely fill the tooth cavity.

The chamber 40 of container 16 is filled with amalgam 17 or other toothfilling material before the container is secured to the housing ofinstrument 1. With compacting element 46 extending through and closingopenings 43 and 45 of the container, the dentist can fill chamber 40with amalgam which has been recently mixed in a separate vessel. Theplug or piston 41 is inserted into the chamber before the container ismounted on the tool. Alternatively, the container assembly shown at FIG.5 including compactor element 46 and piston 41 can be pre-filled withthe ingredients necessary to form the amalgam and the entire containerassembly can be shaken with the usual amalgam mixer just before thedentist uses the instrument to fill a tooth.

In view of the foregoing explanation it is apparent that the dentalinstrument of this invention provides for rapid filling of toothcavities without the need for an assistant. Since the compacting elementis extended after each quantity of amalgam is dispensed, the dentist canimmediately press the amalgam into the cavity without removing theinstrument from the patients mouth. This arrangement greatly decreasesthe time required to fill a tooth, and where the container 16 ispre-filled with the ingredients to form the amalgam, the dentist needonly place the container 16 in the amalgam mixer or shaker immediatelybefore he begins filling a tooth. While amalgam sets quickly after it ismixed, the dentist need not be concerned about cleaning container 16since the container is quite inexpensive and can be discarded after use.Since the compacting element 46 is a part of the container assembly, thecontainer and compactor element can be sterilized and maintained in asterile package until the container 16 is used. Alternatively, theopenings 43 and 45 can be sealed with a suitable plastic film and thedentist can select a desired compacting element and simply force samethrough the openings 43 and 45 before mixing the ingredients in chamber40.

While a preferred embodiment of a dental instrument in accordance withthis invention has been shown and described, it is to be understood thatnumerous changes can be made in the disclosed construction withoutdeparting from the scope of this invention as disclosed herein and setforth in the appended claims.

What is claimed is:

l. A tooth filling material container adapted to be releasably connectedto a dental instrument for dispensing and compacting the dispensedmaterial comprising a casing having a chamber adapted to receive toothfilling material and having a dispensing opening communicating with saidchamber, and compactor-ejector means, initially closing the dispensingopening, for opening and closing the dispensing opening and for ejectingtooth filling material through the dispensing opening, said meanscomprising a compacting-ejecting element movable between a retractedposition in which said dispensing opening is opened and an extendedposition in which the dispensing opening is closed and the compactingelement is exposed to tool the dispensed tooth filling material, saidcompacting element including means thereon for mechanically releasablyconnecting the compacting element to an operating mechanism of a dentalinstrument with which the container is used so that the container andcompacting element can be installed on and removed from the instrumentas a unit with the compacting element closing the dispensing openingwhen the container is separated from the instrument.

2. A filling material container according to claim 1 wherein saidchamber is elongated, and said casing includes guide means for guidingsaid compactingejecting element along a predetermined path duringmovement between said retracted and extended positions.

3. A filling material container according to claim 2 wherein said guidemeans includes the sides of a second opening aligned with saiddispensing opening along the path of travel of said compacting-ejectingelement.

4. A filling material container according to claim 3 wherein said secondopening and said dispensing opening are aligned transversely of saidchamber.

5. A filling material container according to claim 1 which furtherincludes movable means within said chamber for forcing amalgam towardsaid dispensing opening.

6. An amalgam container according to claim 5 wherein said casing has anadditional opening communicating with said chamber and spaced from saiddispensing opening, said chamber has a uniform crosssectionalconfiguration along the portion of its length adjacent said secondopening, and said movable means includes a piston closing saidadditional opening and movable through said chamber to forcetooth-filling material to said dispensing opening.

7. A dental instrument for dispensing and compacting a tooth fillingmaterial comprising a housing, a container having a chamber adapted toreceive tooth filling material and mounted on said housing, saidcontainer having a dispensing opening, a compacting-ejecting devicemovable between a first position in which said dispensing opening isopened and a second position in which said dispensing opening is closedand said compacting-ejecting device is extended and has an end face anda side face exposed for tooling tooth filling material dispensed fromthe container, and means for selectively moving said compacting devicebetween said first and second positions and for locking the compactingdevice in its extended position.

8. A dental instrument according to claim 7 which further includes meansfor vibrating said compacting device.

9. A dental instrument according to claim 7 which further includes meansfor releasably securing said container to said housing.

10. A dental instrument according to claim 7 wherein said means formoving said compacting device between said extended and retractedpositions and for locking the compacting device in its extended positionincludes cam means for locking said compacting device in said extendedposition.

11. A dental instrument according to claim 10 wherein said cam meansincludes a cam plate within said housing, means for moving said camplate to a compacting device locking position, and means for selectivelyoperating said cam plate moving means.

12. A dental instrument according to claim 7 which further includesfollower means for urging tooth filling material in said chamber towardsaid dispensing opensaid container is releasably secured to saidhousing, and said compacting device and said means for moving saidcompacting device include cooperating means for releasably connectingsaid compacting device to said compacting device moving means.

15. A dental instrument according to claim l4 wherein said cooperatingmeans include interengaging slip fit slot and projecting means on saidcompacting device and said compacting device moving means.

1. A tooth filling material container adapted to be releasably connectedto a dental instrument for dispensing and compacting the dispensedmaterial comprising a casing having a chamber adapted to receive toothfilling material and having a dispensing opening communicating with saidchamber, and compactor-ejector means, initially closing the dispensingopening, for opening and closing the dispensing opening and for ejectingtooth filling material through the dispensing opening, said meanscomprising a compacting-ejecting element movable between a retractedposition in which said dispensing opening is opened and an extendedposition in which the dispensing opening is closed and the compactingelement is exposed to tool the dispensed tooth filling material, saidcompacting element including means thereon for mechanically releasablyconnecting the compacting element to an operating mechanism of a dentalinstrument with which the container is used so that the container andcompacting element can be installed on and removed from the instrumentas a unit with the compacting element closing the dispensing openingwhen the container is separated from the instrument.
 2. A fillingmaterial container according to claim 1 wherein said chamber iselongated, and said casing includes guide means for guiding saidcompacting-ejecting element along a predetermined path during movementbetween said retracted and extended positions.
 3. A filling materialcontainer according to claim 2 wherein said guide means includes thesides of a second opening aligned with said dispensing opening along thepath of travel of said compacting-ejecting element.
 4. A fillingmaterial container according to claim 3 wherein said second opening andsaid dispensing opening are aligned transversely of said chamber.
 5. Afilling material container according to claim 1 which further includesmovable means within said chamber for forcing amalgam toward saiddispensing opening.
 6. An amalgam container according to claim 5 whereinsaid casing has an additional opening communicating with said chamberand spaced from said dispensing opening, said chamber has a uniformcross-sectional configuration along the portion of its length adjacentsaid second opening, and said movable means includes a piston closingsaid additional opening and movable through said chamber to forcetooth-filling material to said dispensing opening.
 7. A dentalinstrument for dispensing and compacting a tooth filling materialcomprising a housing, a container having a chamber adapted to receivetooth filling material and mounted on said housing, said containerhaving a dispensing opening, a compacting-ejecting device movablebetween a first position in which said dispensing opening is opened anda second position in which said dispensing opening is closed and saidcompacting-ejecting device is extended and has an end face and a sideface exposed for tooling tooth filling material dispensed from thecontainer, and means for selectively moving said compacting devicebetween said first and second positions and for locking the compactingdevice in its extended position.
 8. A dental instrument according toclaim 7 which further includes means for vibrating said compactingdevice.
 9. A dental instrument according to claim 7 which furtherincludes means for releasably securing said container to said housing.10. A dental instrument according to claim 7 wherein said means formoving said compacting device between said extended and retractedpositions and for locking the compacting device in its extended positionincludes cam means for locking said compacting device in said extendedposition.
 11. A dental instrument according to claim 10 wherein said cammeans includes a cam plate within said housing, means for moving saidcam plate to a compacting device locking position, and means forselectively operating said cam plate moving means.
 12. A dentalinstrument according to claim 7 which further includes follower meansfor urging tooth filling material in said chamber toward said dispensingopening.
 13. A dental instrument according to claim 7 wherein said meansfor selectively moving said compacting device between said extended andretracted positions includes a lever engaging said compacting device,means for locking said lever in said extended position of saidcompacting device, and means for operating said locking means, saidoperating means comprising selectively actuable motor means carried bysaid tool, and manually operable means for selectively operating saidmotor means.
 14. A dental instrument according to claim 7 wherein saidcontainer is releasably secured to said housing, and said compactingdevice and said means for moving said compacting device includecooperating means for releasably connecting said compacting device tosaid compacting device moving means.
 15. A dental instrument accordingto claim 14 wherein said cooperating means include interengaging slipfit slot and projecting means on said compacting device and saidcompacting device moving means.